@primary-color:#000;
@primary-bg:#F5F7F9;
.float-l{
    float: left;
}
.float-r{
    float:right;
}
.clear-fix{
    &:before{
        content: ' ';
        display: block;
        width: 100%;
        height: 0;
        overflow: hidden;
        clear: both;
        visibility: hidden;
    }
    zoom: 1;
}
.border-half{
    position: relative;
    &:after{
        content: ' ';
        display: block;
        position: absolute;
        bottom: 0;
        left: -50%;
        width: 200%;
        height: 1px;
        transform: scale(.5);
        background:@primary-color;
    }
}